1. Field of the Invention
The present invention relates to an organic EL display device.
2. Description of the Related Art
In recent years, an image display device (hereinafter referred to as “organic EL (electro luminescent) display device”) using self-luminous bodies called “organic light emitting diodes” has been input into practical use. As compared with a conventional liquid crystal display device, the organic EL display device not only is excellent in visibility and response speed, but also requires no auxiliary lighting device such as a backlight because of the use of the self-luminous bodies. Therefore, the organic EL display device can be further thinned.
As a method of conducting color display in the organic EL display device of this type, there are a method in which a light emitting element emits light of three colors of R(red), G(green), and B (blue) for each of pixels, a method in which the light emitting element emits light of white, and color filters in each pixel transmit respective wavelength ranges of three colors of RGB, and a method in which those methods are combined together.
JP 2001-312223 A discloses that in order to form an organic EL material with a uniform film thickness, electrode holes are embedded with an organic resin material to form a protective portion. JP 2003-091246 A discloses that contact hole portions are covered with and smoothed by an insulator layer or a conductor layer to uniform the thickness of the organic EL layer, against the same problem as that in JP 2001-312223 A. JP 2009-301058 A discloses that contact holes are embedded with a conductor, and the conductor is brought into contact with metal films which are electrodes from the viewpoint of such a problem that an area in which TFTs and lines are formed does not transmit light.